Electric fuse.



T. E. MURRAY.

ELECTRIC FUSE.

APPLICATION FILED FEB. 10, 1913.

Patented D60. 8,1914.

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THOMAS E. MURRAY, or Imwl Yonx, N. Y.

ELECTRIC FUSE.

Specification of Letters Patent.

I Patented Dec. 8,1914.

Application mea February 1o, 191s. serialize. 147,320.

To all whom t mayoncern Be it known that I, THOMAS E. MURRAY, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented a certain new and useful Improvement in Electric Fuses, of which the following is a speciication.

The invention relates to electric fuses, and consists, rst, in the construction of the carrier bar and fuse strip thereon-second, 1n the dlspositlon of said fuse carrier 1n the case, so as to be readily insertible into and removable therefrom-and third., in the means for determining the blowing of the fuse, without opening the case.

In the accompanymg drawings- Figure 1 is an elevation of my device. Fig. 2 is a longitudinal section' on the line m of Fig.

1. Fig. 3 is a perspective view of the carrier bar, fuse strip and covering plate. Fig. Lljis a longitudinal section of the carrier bar, showing a single fuse strip thereon. Similar numbers of reference' indicate like parts.

The'carrier 1 is a bar of fiber or other insulating material, preferablyr having shallow channels on both sides Iand inthe ends,

l. in which channels the fuse stri 2 is secured.

Said strip may be made annu ar by soldering or otherwise uniting its ends, as shown Y at 3. The strip is preferably made of a width to ll the channels, so that its lateral displacement on the carrier is thus prevented. At about the middle of the carrier is an aperture 4. The parallel parts of the strip where' they cross said aperture may be.

contracted, as shown at 5, to localize the blowing point/ .a1

6- is a cylindrical vcase of ber or other insulating material, onn which are secured the metal "end caps 7 ,"8. The cap 7 has an elongated transverse opening through which the carrier bar is slidable. The cap 8 has a larger opening, which is closed by a plate 9, also of insulating material, on the inner face of which are guide projections 10. In the plate 9 is an openin through which the carrier bar 1 is also s idable.

In assembling the device, the plate 9 being removed and the fuse strip 2 bein in 'position on the carrier bar 1, -the carrier ar is insertedinto the case through the opening in cap 7, until a split pin 11, previously Serted through an opening in the wall of the casing. A loop is made on the end of said cord which is slid down on the carrier bar until it enters the notches forming the contraction in the fuse strip. The cord is then pulled taut, and secured to the outside of the case, preferably by a disk of gummedpaper- 14. Thefilling of pulver-ized refractory material isthenl put into the case through the opening in cap 8,1and when the case is filled, the plate 9 1s passed over the end of the carrier bar and placed in contact with the'outer face of cap 8. A split pin 16 entering another opening in carrier bar 1 holds plate 9 in position.

This device gets rid of the usual troublesome and expensive soldering of the fuse strip to the end caps, common in cartridge fuses of this eneral type. The carrier bar with its attac ed fuse strip is easily inserted, and as easily removed. All that is needed to release 1t is to take out one of the split pins. The cord 13 is a means of finding out whether the fuse strip has blown or not, without opening thev case. If the fuse has blown, the loo on the fuse strip will be released so that t e cord can-be drawn out of the-case by pulling on its outer exposed port-ion. If the fuse has not blown, the cord cannot be pulled out.

The arrangement of the fuse strip shown in Fig. 2, completely encircling the carrier bar, provides a double fuse. If a single fuse is desired, the ends of the strip are not brought together on one side of the carrier bar, but, as indicated in Fig. 4, are left separated and secured to said bar in any suitable way.

I claim:

1. A tubular case, end lates thereon hav-` ing openings, a straig t removable bar` longer than said case and extending through and slidable in said openings, anda fuse strip secured longitudinally on said Qbar.

2. A tubular case, end plates thereon having Iopenings, a straight removable bar longer than said case and extending through and slidable in said openings, and a fuse strip secured longitudinally upon said bar and having its end portions folded over the extremities oflsaid bar outside of said case. 3. A case, filling material, end caps on said case having openings, the opening in one of said caps being larger than the opening in the other cap, a removable plate coverlng said larger'opening and itself having and slidable in saiil smaller cap opening f and said plate` o enng, a fuse strlp secured upon and exten inglon itudinally to said bar, and means onsaid ar ,for preventing 15 endwise' movement thereof.

'.VIntestimony whereof I have aix'eim'y 'signature vin presence of two witnesses.'

l' THOMAS E. MURRAY. Witnesses: A

GERTRUDE T; Ponm, MMT. MCG-Amr., 

